Introduction: Heavy Duty Work Desk

About: I'm a mechanical engineering student at the University of Dayton. I love utilizing fundamentals and principals presented in the classroom to ideate and produce practical solutions to common problems. i.e. I ha…
This desk was built for a fried who does IT work and needed something sturdy, but modular construction to permit repeated and simple tear down/setup (for moving purposes). He was set on a standing desk with tons of surface area for paperwork. We decided to supsend his monitors with the original visa mount he was using. In order to provide ample desktop area and lower shelf storage area I finalized the dimensions of the desk as 40" tall x 30" deep x 72" wide. The final design was made up of essentially a 3 components  (4) 4x4 legs, (2) 2x4 frames, and a composite OSB/HardBoard topper. The final SketchUp Design can be seen in image 1. The components are color coded to emphasize the modularity of the desk--red is the upper/lower shelves, black is the leg support, and gray is the topper (image 2).

Tools Used:
Tape, Square, Level
Miter Saw (Chop Saw)
Cordless and Corded Drill
1/8 inch drill bit and 3/16 spade drill bit
Ratchet and Socket

Materials Used:
See attached Excel Document 
Also used several 2.5 inch Coarse Thread Wood Screws

Step 1: Step 1. Cut Lumber to Length

First, cut the 4x4s in half, resultingin a total of (4) legs measuring 48" long.
Second, cut (4) 2x4s to 69" in length.
Third, cut (4) 2x4 pieces to 30" in length.
Fourth, cut (10) 2x4 pieces to 27" in length.
Last, cut (8) 2x4 pieces to 3" in length for frame support until the carriage bolts are tightened down.
            
 

Step 2: Step 2. Construct Upper and Lower Frame

The upper and lower frame are the same dimension and construction so you will build one then repeat that procedure for the second one.

First lay out the 2x4 pieces you cut to length in the last step in the same configuration as image 1. Make sure everything fits nice and snug.

Next pre-drill and fasten the corners of the frame where the 69" and 30" pieces come together. 

Once you have the box made, supplement this box with a 27" cross member 3 and 9/16" from the inside of the 30" ends...like image 2. Image 3 shows how I made sure the frame would be snug up against the 4x4 legs. I would dry fit the 4x4 leg into its slot before fastening these 27" members.

Lastly, add the remaining (3) 27" cross members to the frame at even intervals between the previously added members.

Repeat this process for a second frame. Should look like image 4.

Tip: If you have two drills (cordless/corded) or a quick change driver set use it. Here I used my corded drill to pre-drill where I intended to fasten the joints to prevent splitting. Then I would use the cordless dewalt to drive home the 2.5 inch wood screw...much quicker this way.

Step 3: Step 3. Add Temporary Supports to Leg Members

I added 3" 2x4 pieces so their tops were at 36.5 inches and thus the top of the 2x4 frame would be at 40 inches. The supports are not necessary for the lower shelf/frame but can be useful if the space between your frame and the 4x4 legs is too large, allowing the frame to slide freely up and down.

Step 4: Step 4. Assemble the Desk

This involved a few steps.

First I laid the lower frame on the ground as a base and as way of keeping the 4x4 legs from falling over. The legs did not fall over because they fit so snug into their respective slots. 

Next, I carefully lifted the upper frame above the legs, centered it, and slowly lowered it until it fit right over the top of the 4x4 legs. The fit was tight so I used a scrap piece of wood and hammer to strike the upper frame into position. I tapped the frame at each corner, iteratively, until the frame was resting flush on the temporary supports.

Once the frame was at the desired height, I needed to drill the holes where the carriage bolts secure the frame to the 4x4 legs.

Once the holes are drilled, put in the carriage bolts, the washer and top it off with the hex nut.

After this, I flipped the whole desk over like image 9 and tapped the "bottom" frame (now on top) down until there was 2 feet of space between the top and bottom frames. Then I repeated the drilling and fastening process executed on the top frame.

Step 5: Step 5. Add OSB/Hardboard Sheet

During this step I used a circular saw to cut out (2) sheets of OSB and (2) sheets of Hardboard at 30"x 72". Then at each corner I cut out 5"x 5" squares to accommodate the leg posts. When adding the lower shelf topper (OSB) make sure the diagonal distance in image 1 is greater than the topper's width...otherwise the topper will not fit.

Step 6: Step 6. Commission Your Hardy Desk

In summary, the heavy duty work desk created in this instructable proved to be completely rigid and wobble free, yet simple enough to disassemble and transport via conventional means. In order to disassemble the desk a total of 16 carriage bolts need removed and two shelves tapped with a mallet until they slide off the leg posts. Honestly the desk could be transported in three whole parts.--the upper shelf, lower shelf, and the 4 leg posts. To disassemble/assemble one needs a ratchet, mallet, and a flat head screw driver helps to drive out the carriage bolts. That's it...simple, mobile, heavy duty, and long lasting.